package com.android.tutor;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.LinearGradient;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Bitmap.Config;
import android.graphics.PorterDuff.Mode;
import android.graphics.Shader.TileMode;
import android.graphics.drawable.Drawable;
public class ImageUtil {
	
	//放大缩小图片
	public static Bitmap zoomBitmap(Bitmap bitmap,int w,int h){
		int width = bitmap.getWidth();
		int height = bitmap.getHeight();
		Matrix matrix = new Matrix();
		float scaleWidht = ((float)w / width);
    	float scaleHeight = ((float)h / height);
    	matrix.postScale(scaleWidht, scaleHeight);
    	Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
		return newbmp;
	}
	//将Drawable转化为Bitmap
	 public static Bitmap drawableToBitmap(Drawable drawable){
	    	int width = drawable.getIntrinsicWidth();
	    	int height = drawable.getIntrinsicHeight();
	    	Bitmap bitmap = Bitmap.createBitmap(width, height,
	    			drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
	                        : Bitmap.Config.RGB_565);
	    	Canvas canvas = new Canvas(bitmap);
	    	drawable.setBounds(0,0,width,height);
	    	drawable.draw(canvas);
	    	return bitmap;
	    	
	    }
	 
	 //获得圆角图片的方法
	public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){
		
		Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap
				.getHeight(), Config.ARGB_8888);
		Canvas canvas = new Canvas(output);
 
		final int color = 0xff424242;
		final Paint paint = new Paint();
		final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
		final RectF rectF = new RectF(rect);
 
		paint.setAntiAlias(true);
		canvas.drawARGB(0, 0, 0, 0);
		paint.setColor(color);
		canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
 
		paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
		canvas.drawBitmap(bitmap, rect, rect, paint);
 
		return output;
	}
	//获得带倒影的图片方法
	public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap){
		final int reflectionGap = 4;
		int width = bitmap.getWidth();
		int height = bitmap.getHeight();
		
		Matrix matrix = new Matrix();
		matrix.preScale(1, -1);
		
		Bitmap reflectionImage = Bitmap.createBitmap(bitmap, 
				0, height/2, width, height/2, matrix, false);
		
		Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height/2), Config.ARGB_8888);
		
		Canvas canvas = new Canvas(bitmapWithReflection);
		canvas.drawBitmap(bitmap, 0, 0, null);
		Paint deafalutPaint = new Paint();
		canvas.drawRect(0, height,width,height + reflectionGap,
				deafalutPaint);
		
		canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null);
		
		Paint paint = new Paint();
		LinearGradient shader = new LinearGradient(0,
				bitmap.getHeight(), 0, bitmapWithReflection.getHeight()
				+ reflectionGap, 0x70ffffff, 0x00ffffff, TileMode.CLAMP);
		paint.setShader(shader);
		// Set the Transfer mode to be porter duff and destination in
		paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
		// Draw a rectangle using the paint with our linear gradient
		canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
				+ reflectionGap, paint);
 
		return bitmapWithReflection;
	}
	
}